Answer: in 12 days.
Explanation:
Vannesa receives a basket every 4 days
Tina receives a basket every 6 days.
Both of them received one basket today.
If today is the day "zero"
We know that Vannesa will receive a basket in the day number:
4, other in day number 8, other in the day 12 and so on.
Tina will receive a basket in day number 6, other in the day number 12, other in the day number 18, and so on.
So if we want to calculate in which day both of them wi receive a basket, we need to find the minimal common multiple of 4 and 6.
You can find the minimal common multiple by taking the product between both numbers and dividing it by the maximal common factor between them.
We have that the maximal common factor between 4 and 6 is 2. because:
2*2 = 4
2*3 = 6
then the minimal common multiple is:
4*6/2 = 4*3 = 12
Then in day number 12 (as it is already written above) both of them will receive a basket.